The subject matter disclosed herein relates generally to diagnostic imaging systems, and more particularly to detector collimation in Nuclear Medicine (NM) imaging systems.
In NM imaging, radiopharmaceuticals are taken internally and then detectors (e.g., gamma cameras), typically mounted on a gantry, capture and form images from the radiation emitted by the radiopharmaceuticals. The NM images primarily show physiological function of, for example, a patient or a portion of a patient being imaged.
Collimation may be used to focus the field of view of the detectors. For example, parallel hole collimators may be used. Additionally, converging fanbeam collimators can be used to improve the sensitivity of the detectors over a limited field of view. However, current fanbeam collimators are constructed using a precision cast process that is difficult to perform and expensive. The precise construction is needed because image quality depends on the alignment of tens of thousands of collimator bores that point in slightly different directions. Additionally, because every collimator bore points in a unique direction, reconstruction algorithms that use certain rebinning techniques may cause loss of resolution.